Batten-Spielmeyer-Vogt (BSV) syndrome is characterized by the deposition of autofluorescent ceroid and lipofuscin pigments in the lysosomes of neuronal and peripheral tissues, progressive mental and motor involvement, and blindness. Lipofuscins are also deposited in the neuronal tissues of aging subjects. However, the biochemical mechanism leading to the formation of these pigments is poorly understood. It has been postulated that the formation of these pigments is associated with a breakdown in the cellular defense mechanism(s) against oxidative damage. Peroxidase deficiency has been demonstrated in the leukocytes of several patients with BSV syndrome. The proposed studies will involve the isolation and characterization of peroxidase isozymes, isolation and identification of lipid peroxides and hydroperoxides, and the use of naturally occuring lipid peroxides and hydroperoxides as substrates for peroxidase isozyme determination in the tissues of patients with BSV syndrome. The peroxidase isozymes will be purified to homogeneity and the effect of various activators and inhibitors will be studied. The enzymes included in the cellular defense mechanisms against oxidative damage, and tissue constituents, such as reduced and oxidized glutathione, will be studied in acatalasemicselenium deficient mice and various tissues of patients with BSV syndrome. These studies will lead to a better understanding of the biochemical mechanism(s) of ceroid and lipofuscin pigment formation in BSV syndrome and will give insight into therapy.